Use StrnCat instead of StrCat to avoid target buffer overflow.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Eric Dong <Eric.Dong@intel.com>

git-svn-id: svn://svn.code.sf.net/p/edk2/code/trunk/edk2/IntelFrameworkModulePkg@15797 6f19259b-4bc3-4df7-8a09-765794883524
MdeModulePkg/IntelFrameworkModulePkg: Update PeiCore, SmbiosDxe and IsaSerialDxe to use PcdGetxx() instead of FixedPcdGetxx().

It changes some of the PCD declarations to add more supported PCD storage types and
the change in the PCD access methods is associated with that.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Zeng, Star <star.zeng@intel.com>
Reviewed-by: Kinney, Michael D <michael.d.kinney@intel.com>
Reviewed-by: Gao, Liming <liming.gao@intel.com>

git-svn-id: svn://svn.code.sf.net/p/edk2/code/trunk/edk2/IntelFrameworkModulePkg@15798 6f19259b-4bc3-4df7-8a09-765794883524